Oscillating pump impeller



June 1964 E. M. SMITH ETAL 3,136,257

OSCILLATING PUMP IMPELLER Filed Oct. 26, 1961 FIG. I

OUTLET l INVENTORS EDWARD M. SMITH 5 JOHN A. WALTERJII ATTORNEYS United States Patent 3,136,257 OSCILLATING PUB W IMPELLER Edward M. Smith, Lexington, and John A. Walter III, Bellville, Ohio, assignors to German-Rump Industries, inc, Bellvilie, Ohima corporation of Ohio v Filed Oct. 26, 1961, Ser. No. 147,980 Claims. (Cl. 103-53) The present invention relates generally to oscillating pumps. More particularly, the present invention relates to an improved impeller'constr uction for electro-magnetic oscillating pumps.

Powering an electro-magnetic oscillating pump from the conventional 60 cycle A.C. line current creates many problems because of the correspondingly high rate of oscillation of the pump impeller.

.One of the most difficult problems attendant upon the construction of such a pump is the provision of valves which can operatively follow the-high rate of oscillation of the impeller and which willrhave effective sealing characteristics as well as a long life.

Furthermore, because the impeller means is driven by electromagnetic forces, it has always been made, at least in part, of a magnetizable metal. Hence, the prior art pumps could not be utilized satisfactorily to pump a corrosive liquid.

Additional difiiculties have arisen because of the necessary springs required to reciprocate the oscillating impeller between the electro-magnetic exciting impulses. In order to maintain the efficiency of the pump the springs sometimes have been tuned to the frequency of the impelling electro-magnetic coil. However, when the oscillating mechanism is thus in phase with the electro-magnetic exciting frequency, the resulting resonance causes the oscillating stroke to increase rapidly unless a counter pressure is supplied. The back pressure of the liquid being pumped normally supplies the required counter pressure. Therefore, if the. pump is operated without liquid there is a tendency for the oscillating stroke to increase to the point of doing considerable damage to the impeller. I-Ieretofore, additional spring means or elaborate valving in minimum pressure chambers have been provided to counter this tendency for an increased stroke.

It is, therefore, an object of the present invention to provide an improved impeller means for an electro-magnetic oscillating pump which is not affected by corrosive materials.

It is a further object of the present invention. to provide such an impeller which incorporates a non-corroding, quick-acting, long-lived and effective sealing valve.

It is a still further object of the present invention to i provide a simplified oscillating control which does not impair the efliciency of the pump and which substantially prevents overtravel of the impeller.

It is a still further object of the present invention to provide an electro-magnetic oscillating pump in which no seals are required.

It is a still further object of the present invention to provide a high-elficiency, reliable electro-magnetic oscillating pump which is simplified in design and inexpensive to fabricate. I

These and other objects of the invention, and further advantages thereof, will become apparent in the following specification and are accomplished by means hereinafter described and claimed.

One preferred embodiment is shown by way of example in the accompanying drawings and hereinafter described in detail without attempting to show all of the various forms and modifications in which the invention might be embodied; the invention being measured by the appended claims and not by the details of the specification.

In the drawings:

FIG. 1 is alongitudinal cross section of an electromagnetic oscillating pump utilizing an impeller means according to the present invention and showing the impeller at the end of the return stroke and just before starting the pumping stroke;

FIG. 2 is a view similar to FIG. 1, showing the impeller at the end of the pumping stroke;

FIG. 3 is an end view of the electro-magnetic oscillating pump taken substantially as indicated on line 3--3 of FIG. 2;

FIG. 4 is a detached side elevation of the improved impeller means; and 1 FIG. 5 is a fra gmentary longitudinal cross section of the improved impeller means taken substantially on line 5-5 of FIG. 4, showing the interior construction of the impeller in a plane at 90 to that depicted in FIGS. 1 and 2. l

An electro-magnetic oscillating pump according to the present invention employs a generally tubular impeller means wholly of a non-corrosive, resilient material. One end of the impeller forms the outlet of the pump and the other the inlet. The outer surface of the medial portion of the impeller is encased by a magnetizable sleeve which performs the function of a solenoid armature and which is fixed on the tubular impeller. On each side of this sleeve the tubular impeller has an axially expansible, or bellows, portion, to allow for reciprocable oscillation of the medial sleeve-encased portion. Interiorly of the sleeve-encased portion of the impeller a winged check valve is formed integrally therewith. When the impeller is in operative position Within a pump a coil spring encircles the impeller means axially between the sleeve and the pump frame and cooperates with the solenoid to provide the necessary reciprocation or oscillation of the impeller.

Referring to the drawings, the improved elastomeric impeller unit, indicated generally by the numeral 10, is adapted to be operatively mounted in an electro-magnetic oscillating pump 11. The pump is built upon a generally U-shaped frame having a base 12and spaced apart parallel legs 13 and 14. A solenoid housing 15 is mounted on the base 12 adjacent leg 13. The end plates 17 and 18 of housing 15 are provided with bores 19 and 20, respectively, which are aligned with each other and also with smaller diameter bores 21 and 22; in the legs 13 and 14, respectively.

A tubular barreled c0re23 having end flanges 24 and 25 extends between end plates 17 and 18, and the inner bore 26 of the core is in registry with the bores 19 and 20 of end plates 17 and 18. The coil windings 28 of the solenoid are wrapped around the radially outer surface of barrel core 23 and electrically connected to arsource of 60 cycle A.C. power supply through a half wave rectifier not shown.

The improved impeller 10 of non-corrosive elastomeric material is received longitudinally within the aligned bores 19, 20, 21, 22 and 26 The outlet nipple 29 extends outwardly beyond leg 13 of the frame sufficiently to permit making connection therewith. An annular flange 30, which is perpendicular to the longitudinal axis surface of leg 13 so that the leg 13 is gripped firmly between the two flanges and 31 to anchor the discharge end of the impeller to the frame of the pump.

An annular flange 32 similar to flange 30 extends radially outwardly from the base of the intake nipple 33 at the opposite end of the impeller unit 10 to engage the outer surface of leg 14. A notched annular spring-seating collar 34 girdles the impeller inwardly of flange 32 and is embraced between flange 32 and opposing buttress flange 35 similar to buttress flange 31 but spaced further inwardly. The notched portion 36 of the collar 34 is preferably received in bore 22.

An armature sleeve 38 of magnetic material fits closely around the medial portion of the impeller and is fixed longitudinally with respect to the impeller by annular lips 39 and 40 extending radially outwardly therefrom and engaging each end of the sleeve 38. An annular anchor flange 41 projects outwardly on one end of sleeve 38 but the remainder of the outer surface of sleeve 38 is slidingly received within barrel 26 and bore 20.

Au axially expansible or bellows portion 42 is provided in the impeller tube between lip 39 and buttress flange 35, as well as between lip 40 and buttress flange 31, to permit oscillation of the sleeve-encased medial or intermediate portion longitudinally of the impeller axis. Although the bellows portions 42 are shown as being formed of semicircular corrugations 43 they can have varying contours, such as a series of angularly disposed folds.

Secured between anchor flange 41 on sleeve 38 and collar 34 is a reciprocating control helical spring 44. The spring assembly, comprising spring 44, the armature sleeve 38 and the oscillating section of tube 10, has a mechanical vibration frequency substantially synchronized with the actuation frequency of the coil 28, but is preferably tuned so that it is slightly out of mechanical resonance therewith. The vibration frequency of the spring assembly may be made substantially synchronous with the resonant or actuation frequency of the coil by adjusting the length of the spring. By tuning it slightly out of synchronization, the magnitude of the stroke of the impeller is augmented because of the substantially synchronous frequency of the spring assembly, and yet a slight resistance due to the detuning is provided, so that if the impeller is operated without fluid, the maximum stroke is suificiently limited to prevent damage to the impeller.

' A transverse spine support 45 extends diametrically across the interior of the impeller at approximately the middle, longitudinally of the medial portion of the impeller 10. The spine further forms the common base about which each of two divergently oriented semielliptical wings 47 and 48 can flap or fold to permit unidirectional flow through the impeller.

The best results are obtained when the impeller is molded as a single unit with the spine 45 and wings 47 and 48 integrally formed therewith. To assure precision seating of the valve wings 47 and 48 against the interior side wall of the impeller 10, the wings and the spine are integrally molded from a non-corrosive elastomeric material, the precise choice of which can best be determined by its individual compatibility with the fluid being pumped.

After the material has been cured, a sharp annular knife edge is inserted a suflicient distance into the discharge end of the impeller unit to sever the outer edge of the wings 47 and 48 from the integrally molded side wall of the impeller up to, but not including the spine 45. The precision sealing of the wings against the impeller walls assured by such a manufacturing process provides an electro-magnetic oscillating pump which is well suited for pumping gas and/ or liquids. Moreover, the negative pressure which can thus be provided on the inlet or suction side of the pump affords such a pump with self-priming characteristic.

Because the impeller means 10 extends entirely through the pump and incorporates both the inlet nipple 33 and [t discharge nipple 39 as an integral part thereof, even the most corrosive pumped fluids cannot contact any of the metallic parts of the device and, moreover, no seals are required in the entire pump structure.

An electro-magnetic oscillating pump of the type disclosed herein operates in the following manner: Since the armature sleeve 38 is fixed to the medial portion of the impeller unit 10, that portion of the impeller is forced to move with the sleeve. The motion of the sleeve is controlled by the magnetic field created by the solenoid windings 28 and the opposing force of the helical spring 44. When the pump is to be operated the solenoid winding is energized through a half wave rectifier AC. power supply source which causes the armautre sleeve to be alternately pulled into the coil and released against the tension of the helical spring 44. These two opposing forces combined cause the armature sleeve, and thus the portion of the impeller encased therein, to oscillate back and forth at 60 cycle frequency. The oscillating movement causes the fluid to be pumped to open and close the wings 47 and 48 in a check valve like fashion, thereby pumping the fluid. It should be noted that because of the rapidity of the oscillation, the efficiency of the wing valves and the momentum of the fluid being pumped, the fluid does not return the impeller between pumping strokes. The volumetric output of the pump can be controlled through its effective range by varying the frequency of the power input to the solenoid.

If it is desirable to reduce the pulsations of the discharge stream, a surge chamber can be incorporated in the discharge line. In most prior art pumps a separate check valve would be required between the surge chamber and the impeller to prevent a reduction of the pumps efficiency caused by a slight leakage or reverse flow past the impeller valve during the pumping stroke. However, the precision seal obtained between wings 47 and 48 and the interior side wall of the impeller when the impeller is made according to the present invention, prevents any such leakage and imparts a full thrust to each volumetric increment pumped. 1

It should be readily apparent that from the foregoing description a highly efficient electro-magnetic oscillating pump can be readily and inexpensively constructed utilizing an impeller means which prevents contact of the fluid being pumped with any of the metallic parts of the pump, which does not require additional sealing means, and

which also accomplishes all the stated objects of the invention.

What is claimed is:

l. A tubular fluid impeller for an oscillating pump comprising, an inlet, an outlet, two axially expansible portions between said inlet and said outlet, a medial portion between said expansible portions adapted to be axially oscillated, said medial portion having interior walls defining a passage therethrough, a transverse integral spine in said intermediate portion, and integral resilient wings extending divergently outwardly from said spine toward said outlet and adapted to sealingly abut said interior walls as said intermediate portion is oscillated in the direction of said outlet.

2. In an oscillating impeller pump having a frame and oscillating means, an impeller tube having an intermediate portion operatively connected to said oscillating means and having inlet and outlet ends securedin saidframe, said tube having axially expansible portions between said intermediate portion and said ends, a transverse integral spine in said intermediate portion, integral resilient wings extending divergently outwardly from said spine toward said outlet end and adapted to open and close as said intermediate portion is oscillated, and spring means on said frame operatively connected to displace said intermediate portion of said impeller tube in the opposite direction to its displacement by said oscillating means,

said spring means having an oscillating frequency sub stantially synchronous with the mechanical resonant frequency of said oscillating means.

3. A tubular fluid impeller for an oscillating pump comprising, an inlet, an outlet, two axially expansible portions between said inlet and said outlet, an intermediate portion between said expansible portions adapted to be axially oscillated, a transverse integral spine in said intermediate portion, and integral resilient wings extending outwardly from said spine toward said outlet and adapted to open and close as said intermediate portion is oscillated.

4. An impeller means for an oscillating pump comprising, a tubular body of an elastomeric material, one end of said tubular body comprising a pump inlet, the other end of said tubular body comprising a pump outlet, two bellows portions in the tubular body between said inlet and said outlet, a medial portion between said bellows portions adapted to be oscillated longitudinally of the body, a transverse supporting spine integral with said medial portion, and integral wings extending outwardly from said spine adapted to open and close against the medial portion as said medial portion is oscillated.

5. An impeller means for an oscillating pump comprising, a tubular body of an elastomeric material, one end of said tubular body having a pump inlet, the other end of said tubular body having a pump outlet, two bellows portions in the tubular body between said inlet and said outlet, an intermediate portion between said bellows portions adapted to be oscillated longitudinally of the body, a transverse integral supporting spine in said intermediate portion, and integral semielliptic wings extending outwardly from said spine toward said outlet adapted to open and close against the intermediate portion as said intermediate portion is oscillated.

6. In an electro-magnetic pump having a frame and a solenoid, an impeller means, said impeller means comprising, a generally tubular body having a passageway longitudinally therethrough, an inlet portion at one end of said body and an outlet portion at the other end of said body, means on said inlet and outlet portions to fasten said impeller LO said frame, two axially extensible portions in said body between said fastening means, a medial portion between said extensible portions adapted to be longitudinally displaced toward said outlet portion by said solenoid, means to return said medial portion after it has been displaced by said solenoid, an integral supporting spine across the passageway within said medial portion, and integral wings extending divergently outward from said spine, said wings so constructed and arranged to close said passageway when said medial portion is displaced toward said outlet portion and open said passageway during return displacement.

7. In an electro-magnetic oscillating pump having a frame and a solenoid, an impeller means, said impeller means comprising, a generally tubular body of elastomeric material having a passageway longitudinally therethrough, an inlet portion at one end of said body and an outlet portion at the other end of said body, means on said inlet and outlet portions to fasten said impeller to said frame, two bellows portions in said body between said fastening means, a medial portion between said bellows portions, an armature sleeve encircling said medial portion, means to fasten said sleeve to said medial portion, said sleeve and medial portion positioned with respect to said solenoid such that energizing said solenoid displaces said sleeve and medial portion toward said outlet portion, means to return said medial portion after it has been displaced by said solenoid, a transverse integral supporting spine within said medial portion, integral semielliptic wings extending divergently outward from said spine toward said outlet portion, said wings constructed and arranged to close said passage when said medial portion is displaced toward said outlet portion and open said passageway during return displacement.

8. In an electro-magnetic oscillating pump having a frame and a solenoid, an impeller means, said impeller means comprising, a generally tubular body of elastomeric material having a passageway longitudinally therethrough, an inlet portion at one end of said body and an outlet portion at the other end of said body, means on said inlet and outlet portions to fasten said impeller to said frame, two bellows portions in said body between said fastening means, a medial portion between said bellows portions, an armature sleeve encircling said medial portion, means to fasten said sleeve to said medial portion, said sleeve and medial portion positioned with respect to said solenoid such that energizing said solenoid displaces said sleeve and medial portion toward said outlet portion, a single spring'means interconnected between said sleeve and said frame to return said medial portion after it has been displaced by said solenoid, and an integral elastomeric check valve within said medial portion, said check valve comprising a transverse spine and integral semielliptic wings extending divergently outward from said spine toward said outlet portion, said wings constructed and arranged to close said passage when said medial portion is displaced toward said outlet portion and open said passageway during return displacement.

9. In an electro-magnetic oscillating pump having a frame and a solenoid, energizable at a cyclic frequency, an impeller means, said impeller means comprising, a generally tubular body of elastomeric material having a passageway longitudinally therethrough, an inlet portion at one end of said body and an outlet portion at the other end of said body, means on said inlet and outlet portions to fasten said impeller to said frame, two bellows portions in said body between said fastening means, a medial portion between said bellows portions, an armature sleeve encircling said medial portion, means to fasten said sleeve to said medial portion, said sleeve and medial portion positioned with respect to said solenoid such that energizing said solenoid displaces said sleeve and medial portion toward said outlet portion, a single spring means interconnected between said sleeve and said frame to return said medial portion after it has been displaced by said solenoid, said spring means having an oscillating frequency substantially in tune with the frequency of said solenoid, an integral supporting spine across the passage within said medial portion, integral semielliptic wings extending divergently outward from said spine toward said outlet portion, said Wings constructed and arranged to close said passage when said medial portion is displaced toward said outlet portion and open said passageway during return displacement.

10. In an electro-magnetic oscillating pump having a frame and a solenoid energizable at a cyclic frequency, an impeller means, said impeller means comprising, a generally tubular body of elastomeric material having a passageway longitudinally therethrough, an inlet portion at one end of said body and an outlet portion at the other end of said body, means on said inlet and outlet portions to fasten said impeller to said frame, two bellows portions in said body between said fastening means, a medial portion between said bellows portions, an armature sleeve encircling said medial portion, means to fasten said sleeve to said medial portion, said sleeve and medial portion positioned with respect to said solenoid such that energizing said solenoid displaces said sleeve and medial portion toward said outlet portion, a single spring means interconnected between said sleeve and said frame to return said medial portion after it has been displaced by said solenoid, said spring means, armature sleeve and movable tube portion forming a spring assembly, said spring assembly having an oscillating frequency substantially in tune with the frequency of said solenoid, and an integral elastomeric check valve within said medial portion, said check valve comprising a transverse spine and integral wings diverging from said spine toward said outlet portion, said wings con structed and arranged to close said passage when said medial portion is displaced toward said outlet portion and to open said passage during return displacement.

References Cited in the file of this patent UNITED STATES PATENTS 8 Pomykata July 2, 1957 Tremblay Dec. 10, 1957 Wellington Sept. 30, 1958 FOREIGN PATENTS Italy Nov. 21, 1938 France Sept. 25, 1939 France Dec. 30, 1950 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No, 3,136,257 June 9, 1964 Edward M; Smith et a1.

It is hereby certified that error appears in the above numbered pat-1 ent requiring correction and that the said Letters Patent should read as 1 corrected below.

Column 4, line 25, after "return" insert with Signed and sealed this 13th day of October 1964.

(SEAL) Attest:

EDWARD J. BRENNER Commissioner of Patents I ERNEST W; SWIDER Altcsting Officer 

1. A TUBULAR FLUDI IMPELLER FOR AN OSCILLATING PUMP COMPRISING, AN INLET, AN OUTLET, TWO AXIALLY EXPANSIBLE PORTIONS BETWEEN SAID INLET AND SAID OUTLET, A MEDIAL PORTION BETWEEN SAID EXPANSIBLE PORTIONS ADAPTED TO BE AXIALLY OSCILLATED, SAID MEDIAL PORTION HAVING INTERIOR WALLS DEFINING A PASSAGE THERETHROUGH, A TRANSVERSE INTEGRAL SPINE IN SAID INTERMEDIATE PORTION, AND INTEGRAL RESILIENT WINGS EXTENDING DIVERGENTLY OUTWARDLY FROM SAID SPINE TOWARD SAID OUTLET AND ADAPTED TO SEALINGLY ABUT SAID INTERIOR WALLS AS SAID INTERMEDIATE PORTION IS OSCILLATED IN THE DIRECTION OF SAID OUTLET. 